Break-away type closure for a container



Dec. 29, 1964 v. G. BIEDENSTEIN ETAL 3,163,317

BREAK-AWAY TYPE CLOSURE FOR A CONTAINER Filed Sept. 24, 1962 3Sheets-Sheet l INVENTORS VINCENT G. BIEDENSTEIN PETER J. DITTO HARRY H.ELLERBROCK BY w a v ATTORNEYS 1964 v. G. BIEDENSTEIN ETAL 3,153,317

BREAK-AWAY TYPE CLOSURE FOR A CONTAINER Filed Sept. 24, 1 962 5Sheets-Sheet 2 FIG.4.

1964 v. G. BIEDENSTEIN ETAL 3,163,317

BREAK-AWAY TYPE CLOSURE FOR A CONTAINER 5 Sheets-Sheet 5 Filed Sept. 24,1962 ilnited States Patent i 3,163,317 BREAK-AWAY TYPE {ILUSURE BUR ACQNTAINER 1 Vincent G. Biedenstein, ()verland, Peter J. Ditto, St. Ann,

and Harry E, Ellerbroch, Weodson Terrace, Mo., as-

signers to RC. (Ian Company, (lverland, Mm, a corporation of itiissouriFiled Sept. 24, 1962, Ser. No. 225,454 6 Claims. (Cl. 220-54) Thisinvention relates to'a break-away type closure for a. container, andmore specifically to a container closure preferably of a flexibleplastic, such as polyethylene, so constructed as to be initiallyfractured at a predetermined line of weakness near its perimeter byapplying a force in one direction and subsequently torn away by a forceon the closure in approximately the opposite direction.

For many years, products of petroleum, or the like, have beenmerchandised in cans of various sizes and shapes and made of metal or offiber. At the present time, there are several cans on the market whichuse a frangible type of closure opened by a tool of some kind.

It is the principal object of this invention to provide a frangibleclosure for a can which can be removed without the use of tools of anykind.

it is a further object of this invention to provide a liquid tight endon a can which has a break-away closure part.

It is a further object of this invention to provide a can end with abreak-away closure part which has the necessary strength to withstandinternal pressure without fracture or seepage, but which may be openedwithout tools by a simple manual manipulation of a pull tab of novelcharacteristics.

It is a further object of this invention to provide a can end closure ofthe break-away type with a means of operation which is small and compactso as to be readily recessed in the can end.

it is still a further object of this invention to provide a break-awaytype of closure for a can which is able to resist considerable strainapplied thereto but which can be easily operated by small forces appliedin a particular way and in a particular sequence. 7

According to this invention, a can end is closed by a can end closurepermanently secured to the rim of the part adjacent, but inside, thescore line and with its free end extending across the cover part. Thepull tab can be relatively stilt or relatively flexible, but, if offlexible material, it is made with a thumb piece at its secured end. Thethumb piece is not absolutely necessary if the tab is made of inflexiblematerial and relatively stiff,

, In either case, the construction of the pull tab is such that as thetab is gripped between thumb and forefinger and rocked toward the scoreline, anv inwardly directed force is applied to the cover part locally,adjacentthe score line, whichproduces initial'breakaway. Thereafter,only a verymoderate amount of pull is necessary to completely separatethe cover part from the can end closure; During this separatiomthe coveris flexed as it is peeled away, and a tearing action takes place alongthe score line, thus, minimizing the effort required by concentratingthe shearing action as the separation prograsses. Because of theconstruction of the pull tab, the break-away action is far moreefiective than can be obtaincd by a simple outwardly directed pull onthe' tab. As a result, the closure can be constructed far stronger3,163,317 Patented Dec. 29, 1964 ice ' the type requiring a tool toopen. It is'recognized that the principle described here resembles thatheretofore applied in the construction of tear strips in metal cans,

but, so far as is now known, the described application here,thedescribed use here, and the described results obtained from this useand application are believed novel.

Otherobjects and advantages of this invention will appear in thefollowing detailed description which is in such clear, concise and exactterms as will enable any person skilled in the art to make and use theinvention when taken with the accompanying drawings, forming a partthereof, and in which: 7 7

FIG. 1 is a side elevation in section of the top part of a can equippedwith a closure constructed in accordance with this invention;

FIG. 2 is a top plan View of FIG. 1;

FIGS. 3, '4 and 5 are schematic views illustrating operation of theclosure shown in FIGS. 1 and 2; 5

FIG. 6 is an elevational view in section illustrating a modified form ofthe invention;

FIG. 7'is a side elevational View in section illustrating. anothermodified form of the invention having a relatively flexible tab as inthe prior embodiments;

FIG. 8 is aside elevationalview in section illustrating the form thedrawings.

Turning now to FIG. 1 a can body 10 is surrounded by cylindrical canwalls 11 to form a container.- The lower end of the container may beclosed by any suitable type of closure and the wall 11 formed ofeithermetal or fiber. The closure, according to this invention, issecured to the top open end of the container around the rirn'thereoi.This can end closure isgenerally indicated by the reference character 12and includes a metal cover part 13 ofcircular form having its outer edge14 crimped onto the rim of can end wall 11. Can end closure 13 has acentral aperture surrounded by a head 15 which is rolled onto a rimportion 16 of a break-away cover part.

The break-away cover part 18 is preferably made of a flexible material,such as polyethylene, and comprises. a cover part lii surroundedby anupstanding rlm'16; The rim 16 is tightly clinched by the rolled edge 150f V the can end closure13. Cover part 18 is'surroundedby a score, suchas Zil, at-the 'peripherythereof between the cover. part 18 and theupstanding rim 16; Preferably, the score Ztlis made opposite the corner21 between the break-away cover part 18 and the upstanding rim. Thetrolled edgeld of the can end closure 13 is formed so as to provide adepending lip 22 extending adjacent to the score line 2% on the oppositesurface of the break-away 5 cover part 13. Inthe form shown, the can endclosure 13 is of sheet metal, and, consequently,- the rolled bead ,15formsa rigid support attire -periphery oi the break-f i enough toproduce a local fracture at the score line 320 adjacent the end ofportion 326. 'Thereafter, the pull The pull tab 25 is secured to theoutside surfaceof the break-away cover part 18 adjacent its score line29 and extends across the break-away cover part 118 from the point orzone in which the pull tab 25 is secured. Formed integral with the pulltab 25 is an upstanding thumb piece or. rib 26 which is positionedclosely adjacent'to the score 20 which forms the line of weakness at theperimeter of the breakaway cover part 18. The surfaces of the pull tab25 may be suitably corrugated to obtain a firm finger grip.

As shown in FIG. 2, the arrangement of the thumb piece 26 with respectto the pull tab 25 is such that when the latter is gripped between thethumb and forefinger, the end of the thumb will naturally press againstthe ribshaped thumb piece 26.

As shown in FIGS. 3-5, the manner in which the tab is naturally grippedbetween the fingers produces the desired forces for the successfuloperation of the action of separating the break-away cover part 18 fromthe can end closure 13. As shown in FIG. 3, tab is gripped between thethumb and forefinger with the thumb against the thumb piece 26. The handof the operator is then v5, which will peel the cover part 18 along theline of weakness 20 completely severing the break-away cover part 18from the can end closure 13.

In the modified form of the invention shown in FIG. 6, correspondingparts are indicated by the same reference character with 100 added. Inthis modification, the break-away cover-part 118 is surrounded by anupstanding rim 116 which has an outside diameter snugly fitting withinthe'rirn of the can wall 111. The metal bead 1 14 is clinched to the rimof the can wall 111 at its outer periphery and to the upstanding rim 116at its inner periphery fastening the closure securely to the open end ofthe can body 116. The operation'of the modiiication shown in FIG. 6 isthe same as that above described. The preferred location for the scoreline 129 is opposite the corner 121, but it can be located adjacent thecorner as in.FIG.'6. a

In the modification'shown in FIG. 7, parts corresponding with those inthe prior embodiments are indicated by the same reference character with200' added. The modificatiom shown in FIG. 7, differs only in the, shapeof the thumb piece. The tab is a flexible strip, as in prior devices,and the thumb piece 226 is a plurality of ribs or corrugations insteadof a single rib. Otherwise,

the same description applies to the parts in FIG. 7 as in "thepreviousillustrations in the drawings.

7 In the modificationshown in FIGS; 8-11, parts corresponding generallyand exactlylwithxthose in the prior forms are indicated by the samereference character with material, or relatively inflexible'inconstruction. The tab,

therefore, is shown at 325 of thicker section as compared to parts 25,125 and 225. Furthermore, the portion 326 exerted on'the tab 325 tearsthe closure along the score line to completely separate the tear top318.

The successful operation of any of the above described forms of theinvention depends upon flexibility of the material in the tear top 18and the rigidity contributed to the tear top 18 adjacent the score line20 by bead 15. It has been discovered that these features produceconcentration of the forces applied by pull on the tab to a focal pointon the score line and make initial fracture possible by the applicationof reasonable manual force to a closure with suflicient strength towithstand shipping and handling stresses. If the tear top 18 is notflexible, or the outer edge by the score line 29 is not infiexibly held,the forces required for fracture and removal become so great that a' manof ordinary strength cannot always exert the manual force required.Thus, the advantage of easy opening without tools is lost and the deviceloses its competitive advantage with other forms of trangible closures.These two features of the closure also contribute to removal after localfracture. If the tear top 13 is not readily bendable, it will not teareasily along the'score line it) and it will not tear at all unless theedge 16 is held rigidly.

In the modification shown in FIG. 12, corresponding parts are given thesame reference character with 400 added. With respect to all forms, thescore lines 20, 120, etc., are located opposite the corners 21, 121,etc. This may also be true of the form shown in FIG. 12, however, theupstanding rim 416 may also be provided with a score line, such as 439'as in FIG. 12, opposite the free edge of the bead 415 so that upwardpull on the tab will cause the flexible closure to buckle at the corner21 and fracture at the score line when bent around the sharp freeedge'of bead 415. 'Thus, if one unfamiliar with the manner of operationof the tear top 418 should exert merely a straight pullrather than thepush pull action intended, the closure would fracture anyway. This is sobecause a straight pull on tab 425 would press the sharp edge of metalat the free edge of the bead 415 into a weakened portion of the plasticclosure. This will cause the initial fracture, and, as the flexibleplastic is bent against this metal edge progressively, it will continueto tear around the bead 415 to fully separate.

Changes in and modifications of the construction described may be madewithout departing from the spirit of our invention or sacrificing itsadvantages.

is thicker and, therefore, stiffer so as toforrn a relatively 32 5 andthe break-away nection at 326 and produces an oppositely directeddownward force at the end of 326 at the score line -320. This .force ne;ngqniunc qn wit hum P e e 7 i tab 325 flexesthe cover part 318 due tothe stiffer-com.

Having thus described the invention, what is claimed and desired to besecured by Letters Patent is:

1. 'In a closure for a container having an open end with said closuresecured permanently to said open end bymeans forming a liquid tightjoint, and a flexible plastic break-away cover partdefined by a meansforming a line of weakness in the material of said closure surroundingsaid cover part, the improvement comprising,

(1) a flexible finger operated pull tab of plastic material located onthe outside 'of' said cover part havinitial fracture in said closure atsaid portion of said line of weakness. 2. In a closure for ac ontainerhaving an open end with said closure secured permanently {to said openend by means forming a liquid tight joint, andabretk-away cover part offlexible, rubber-like plastic material defined y m ans f rm n a l ofWeakne in t e m t ri l j of said closure surrounding said cover part,the improvement comprising,

(1) a flexible, finger operated pull tab located on the outside of saidcover parthaving one end secured V to said cover pant adjacent to aportion of said line of weakness and its free end projecting across saidcover part away from said portion, toward another portion of said lineof Weakness, and I (2) a thumb piece at the point of attachment betweensaid pull tab and said cover part operative when said pull tab isgrasped between the fingers of the user and its free end lifted awayfrom the outside of said cover part to create a force acting on saidcover part in the opposite direction on said line of weakness to produceinitial fracture in said closure at said portion of said line ofWeakness.

3. In a closure for a container having an open end with said closurerigidly secured in a permanent manner to said open endby means forming aliquid tight joint, and :a break-away cover part of flexible, plasticmaterial defined by means forming a line of weakness in the material ofsaid closure surrounding said cover part, the improvement comprising, 7

(1) a flexible, finger operated pull tab located on the outside of saidcover part having one end secured to said cover part adjacent to aportion of said line of weakness and its free end projecting across saidcover part away from said portion toward another portion of said line ofweakness, and

(2) means including a protruding thumb piece at the attached end of saidpull tab operative when said pull tab is grasped between the fingers ofthe user and its free end lifted away from the outside of said coverpart to create a force acting on said cover part at said line ofweakness in the opposite direction to produce initial'fracture in saidclosure at said portion of said lineof weakness.

4. In the combination of a container having an open end, the improvementcomprising,

(1) a cover part made of flexible material capable of bending andincluding, Z

(2) a rim portion surrounding said cover part formed of thesamebend-able material,

(3) a ring-shaped metal part secured to the open end of said containerat its outer edge and having a rolled bead at its free inner edgecrimped on said rim portion to form a rigid support against bending,

(4) a score line forming a weakened section in said cover part adjacentsaid rolled bead for defining a ine of fracture between the bendable andnon-bendable portions of said cover part, and

(5) a pull tab attached'to said bendable cover part adjacent said scoreline and operative when tensioned to produce bending of the bendablematerial in said cover portion with respect to the rigidly supported rimportion and fracture along said score line.

5. In the combination of a container having an open 6 end, and a tearaway type of closure secured to said end, the improvement comprising,

(1) a cover part'made of flexible material capable of bending andincluding, i V

(2) a rim portion on said cover part formed of the same bendablematerial,

(3) a ring-shaped metal part secured to the open end of said containerat its outer edge and having a bead at its free inner edge crimped oversaid rim portion to form a rigid support against bending, and a sharpshearing edge disposed at the edge of said cover part,

(4) a score line forming a weakened section in said cover part adjacentsaid bead for defining a line of fracture, and l (5) a pull tab attachedto said bendable cover part adjacent said score line and operative whentensioned to produce bending-of the bendable material in said cover partadjacent said tab against said sharp shearing edge and initial fracturealong said I score line in said cover part at said pull tab.

6. In the combination of a container having an open end and a tear awaytype of closure secured to said open end, the improvement comprising,

(1) a cover part made of flexible material capable of bending andincluding, a (2) a rim portion around said cover part formed of the samebendable material,

(3) a ring-shaped metal part/secured to the open end of said containerat its outer edge and having a rolled bead at its free inner edgecrirnped on said rim portion to form a rigid support against bending,

(4) a score line forming a weakened section in said cover part adjacentsaid rolled bead for defining a line of fracture between the bendableand non-bendable portions of said cover part, 7

(5) a pull tab attached to said bendable cover part adjacent said scoreline and operative when tensioned to produce bending of the bendablematerial in said cover part with respect to the rigidly supported rim-4O portion to tear said cover part from said rim portion after initialfracture along said score line, and

(6) means on said bendable closure part positioned at said score line tobe pressed inwardly of said con-' tainer When'said tab is grasped andlifted and opera tive to produce initial fracture along said-score line.

References Cited by the Examiner UNITED STATES PATENTS THERON E. CONDON,Primary Examiner.

EARLE J. DRUMMOND, Examiner.

open 7

1. IN A CLOSURE FOR A CONTAINER HAVING AN OPEN END WITH SAID CLOSURESECURED PERMANENTLY TO SAID OPEN END BY MEANS FORMING A LIQUID TIGHTJOINT, AND A FLEXIBLE PLASTIC BREAK-AWAY COVER PART DEFINED BY A MEANSFORMING A LINE OF WEAKNESS IN THE MATERIAL OF SAID CLOSURE SURROUNDINGSAID COVER PART, THE IMPROVEMENT COMPRISING, (1) A FLEXIBLE FINGEROPERATED PULL TAB OF PLASTIC MATERIAL LOCATED ON THE OUTSIDE OF SAIDCOVER PART HAVING ONE END SECURED TO SAID COVER PART ADJACENT TO APORTION OF SAID LINE OF WEAKNESS AND ITS FREE END PROJECTING ACROSS SAIDCOVER PART AWAY FROM SAID PORTION TOWARD ANOTHER PORTION OF SAID LINE OFWEAKNESS, AND (2) MEANS AT THE SECURED END OF SAID FLEXIBLE PULL TABOPERATIVE WHEN SAID PULL TAB IS GRASPED BETWEEN THE FINGERS OF THE USERAND ITS FREE END LIFTED AWAY FROM THE OUTSIDE OF SAID COVER PART TOCREATE A FORCE ACTING ON SAID COVER PART IN THE OPPOSITE DIRECTION TOPRODUCE INITIAL FRACTURE IN SAID CLOSURE AT SAID PORTION OF SAID LINE OFWEAKNESS.